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Erdős problem 15

Is it true that ∑n=1∞(−1)nnpn\sum_{n=1}^\infty(-1)^n\frac{n}{p_n} converges, where pnp_n is the sequence of primes?

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15.lean

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Is it true that ∑n=1∞(−1)nnpn\sum_{n=1}^\infty(-1)^n\frac{n}{p_n} converges, where pnp_n is the sequence of primes?

Note: In the problem statement, pnp_n is the nn-th prime, indexed such that p1=2,p2=3,…p_1=2, p_2=3, \ldots. We 0-index here to reflect how Nat.nth works.

FormalConjectures/ErdosProblems/15.leanErdos15.erdos_151 lineExact file
True ↔ Summable fun k => (-1) ^ (k + 1) * (↑k + 1) / ↑(Nat.nth Nat.Prime k)
OpenStatement only, no proof